Edit in JSFiddle

// FizzBuzz in Javascript
// @author: Larry Battle <http://bateru.com/news>
// @date Nov 30, 2012
// http://bateru.com/news/2012/10/code-of-the-day-fizzbuzz-in-javascript/

var getFizzBuzzStatements = function (len) {
    var j,
    arr = [];
    for (var i = 1; i <= len; i++) {
        switch (i % 15) {
        case 0:
            arr.push("FizzBuzz");
            break;
        case 3:    case 6:    case 9:    case 12:
            arr.push("Fizz");
            break;
        case 5:    case 10:
            arr.push("Buzz");
            break;
        default:
            arr.push(i);
        }
    }
    return arr;
};
var fizzBuzz = function () {
    console.log(getFizzBuzzStatements(100).join("\n"));
};
test("test getFizzBuzzStatements()", function(){
    var fn = getFizzBuzzStatements;
    var expected=[
        1,2,"Fizz",4,"Buzz","Fizz",7,8,"Fizz","Buzz",11,"Fizz",
        13,14,"FizzBuzz",16,17,"Fizz",19,"Buzz","Fizz",22,23,
        "Fizz","Buzz",26,"Fizz",28,29,"FizzBuzz",31,32,"Fizz",
        34,"Buzz","Fizz",37,38,"Fizz","Buzz",41,"Fizz",43,44,
        "FizzBuzz",46,47,"Fizz",49,"Buzz","Fizz",52,53,"Fizz",
        "Buzz",56,"Fizz",58,59,"FizzBuzz",61,62,"Fizz",64,"Buzz",
        "Fizz",67,68,"Fizz","Buzz",71,"Fizz",73,74,"FizzBuzz",
        76,77,"Fizz",79,"Buzz","Fizz",82,83,"Fizz","Buzz",86,
        "Fizz",88,89,"FizzBuzz",91,92,"Fizz",94,"Buzz","Fizz",
        97,98,"Fizz", "Buzz"
    ];
    deepEqual( fn(100), expected );
});

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